Old English spæc "act of speaking; power of speaking; manner of speaking; statement, discourse, narrative, formal utterance; language," variant of spræc, from Proto-Germanic *sprek-, *spek- (source also of Danish sprog, Old Saxon spraca, Old Frisian spreke, Dutch spraak, Old High German sprahha, German Sprache "speech;" see speak (v.))
The spr- forms were extinct in English by 1200. Meaning "address delivered to an audience" first recorded 1580s.
And I honor the man who is willing to sink
Half his present repute for the freedom to think,
And, when he has thought, be his cause strong or weak,
Will risk t' other half for the freedom to speak,
Caring naught for what vengeance the mob has in store,
Let that mob be the upper ten thousand or lower.
[James Russell Lowell, "A Fable for Critics," 1848]
But when men have realized that time has upset many fighting faiths, they may come to believe even more than they believe the very foundations of their own conduct that the ultimate good desired is better reached by free trade in ideas — that the best test of truth is the power of the thought to get itself accepted in the competition of the market, and that truth is the only ground upon which their wishes safely can be carried out. That, at any rate, is the theory of our Constitution. It is an experiment, as all life is an experiment. ... I think that we should be eternally vigilant against attempts to check the expression of opinions that we loathe and believe to be fraught with death, unless they so imminently threaten immediate interference with the lawful and pressing purposes of the law that an immediate check is required to save the country. [Oliver Wendell Holmes Jr., dissent to "Abrams v. United States," 1919]
late 15c. (Caxton), "destroy or derange the order of, throw into confusion," from dis- "not" (see dis-) + order (v.). Replaced earlier disordeine (mid-14c.), from Old French desordainer, from Medieval Latin disordinare "throw into disorder," from Latin dis- + ordinare "to order, regulate," from ordo (genitive ordinis) "row, rank, series, arrangement" (see order (n.)). Related: Disordered; disordering.
1520s, "lack of regular arrangement;" 1530s, "tumult, disturbance of the peace;" from disorder (v.). Meaning "an ailment, a disturbance of the body or mind" is by 1704.
"a word viewed as a constituent member of a sentence," c. 1500, translating Latin pars orationis (see parse). The parts of speech are: Noun, adjective, pronoun, verb, adverb, preposition, conjunction, and interjection. Sometimes article and participle are counted among them.
"nervous disorder peculiar to Siberia, in which the patient mimics everything said or done by another," also often characterized by obscene speech, 1884, from Russian, said to mean literally "to be epileptic." Early writings on it compared it to the latah of South Asia and Malaysia and the Jumpers of Maine.
"to make untidy, put in a state of disorder," 1837, American English, probably a variant of mess in its sense of "to disorder." It was attested earlier (1830) as a noun meaning "disturbance, state of confusion." Related: Mussed; mussing.
late 13c., "mental distress, emotional disorder of the mind, grief," from Old French destorbance (12c., Old North French distorbance), from destourber, from Latin disturbare "throw into disorder," from dis- "completely" (see dis-) + turbare "to disorder, disturb," from turba "turmoil" (see turbid).
Meaning "public disturbance, political agitation" is from c. 1300; that of "violent interruption of peace or unity" is late 14c.; it is the sense in disturbance of the (king's) peace," early 15c.